Patient Characteristics and Outcomes of Type 2 Myocardial Infarction During Heart Failure Hospitalizations in the United States

Background: Type 2 myocardial infarction (MI) is increasingly diagnosed in patients with heart failure (HF). A paucity of data exists pertinent to the contemporary prevalence and impact of type 2 MI in patients with HF. We studied the patient profiles and the prognostic impact of type 2 MI on outcomes of HF hospitalizations. Methods: The Nationwide Readmission Database 2018 was queried for patients with HF hospitalizations with and without type 2 MI. Baseline characteristics, inpatient outcomes, and 30-day all-cause readmissions between both cohorts were compared. Results: Of 1,072,674 primary HF hospitalizations included in the study, 28,813 (2.7%) had type 2 MI. Patients with type 2 MI were more likely to be males (56.5% vs 51.6%; P < .001) and had a higher prevalence of hypertension (94% vs 92.2%; P < .001), prior myocardial infarction (17.1% vs 14.9%; P < .001), anemia (9.1% vs 8.1%; P < .001), chronic kidney disease (55.7% vs 49.4%; P < .001), neurological disorders (9.4% vs 7.3%; P < .001), and weight loss (7.3% vs 5.6%; P < .001). Compared with their counterparts without type 2 MI, patients with HF with type 2 MI had significantly higher in-hospital mortality (adjusted odds ratio [aOR], 1.53; 95% confidence interval [CI], 1.37-1.72), hospital costs (adjusted parameter estimate, $1785; 95% CI, 1388-2182), discharge to nursing facility (aOR, 1.22; 95% CI, 1.15-1.29), longer length of stay (adjusted parameter estimate, 0.53; 95% CI, 0.42-0.64), and rate of 30-day all-cause readmissions (aOR, 1.06; 95% CI, 1.01-1.12). Conclusion: Type 2 MI in patients hospitalized with HF is associated with higher mortality and resource utilization in the United States.